stusql.cs

基于asp.net的网上选课系统

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;
/// <summary>
/// StuSQL 的摘要说明
/// </summary>
   
public class StuSQL
{   
    //连接数据库的字符串
    private string stuConnStr;
    //数据库连接对象
    private SqlConnection stuConn;
    public StuSQL()
	{
		//
		// TODO: 在此处添加构造函数逻辑
		//
	}
    public void Open()
    {
        stuConnStr = "Data Source=.;Initial Catalog=selectCourses;Integrated Security=True";
        //创建数据库连接对象
        stuConn = new SqlConnection(stuConnStr);
        //打开数据库连接
        stuConn.Open();
    }

    public void Close()
    {
        //关闭数据库连接
        stuConn.Close();
    }

    
    public int ExecuteSQL(string str)
    {
        SqlCommand cmd = new SqlCommand(str, stuConn);
        //返回数据库操作影响的行数
        int aff = cmd.ExecuteNonQuery();
        return aff;
    }


    //读取数据库中的数据并存放在一个数据集Dataset里面
    public DataSet GetDataSet(string strComm,String strT)
    {
        SqlDataAdapter ad=new SqlDataAdapter(strComm,stuConn);
        //创建Dataset对象
        DataSet ds=new DataSet();
        //填充数据
        ad.Fill(ds,strT);
        return ds;
    }

    //调用存储过程实现学生选课功能
    public int ElectCourse(string stuid,string cursid)
    {
        //创建数据库操作命令的对象
        SqlCommand cmd=new SqlCommand("ElectCourse",stuConn);
        //指明Sql命令的操作类型是使用存储过程
        cmd.CommandType=CommandType.StoredProcedure;

        //给存储过程添加参数
        SqlParameter stu=new SqlParameter("@StudentID",SqlDbType.NVarChar,50);
        stu.Value=stuid;
        cmd.Parameters.Add(stu);

         SqlParameter  curs=new SqlParameter("@CourseID",SqlDbType.NVarChar,50);
         curs.Value=cursid;
         cmd.Parameters.Add(curs);

        SqlParameter aff=new SqlParameter("@rowaffected",SqlDbType.Int,4);
        //说明该存储过程的参数是OUTPUT类型
        aff.Direction=ParameterDirection.Output;
        cmd.Parameters.Add(aff);

        //执行存储过程
        cmd.ExecuteNonQuery();
        //取得存储过程OUTPUT参数的值作为函数的返回值
        if(aff.Value.ToString()!="")
            return (int)aff.Value;
        else
            return 0;
    }
    //调用存储过程实现学生退选课程功能
    public int CancelCourse(string stuid, string cursid)
    {
        SqlCommand cmd=new SqlCommand("CancelCourse",stuConn);
        cmd.CommandType=CommandType.StoredProcedure;

        //给存储过程添加参数
        SqlParameter stu=new SqlParameter("@StudentID",SqlDbType.NVarChar,50);
        stu.Value=stuid;
        cmd.Parameters.Add(stu);
        
        SqlParameter  curs=new SqlParameter("@CourseID",SqlDbType.NVarChar,50);
        curs.Value=cursid;
        cmd.Parameters.Add(curs);

        SqlParameter aff=new SqlParameter("@rowaffected",SqlDbType.Int ,4);
        aff.Direction=ParameterDirection.Output;
        cmd.Parameters.Add(aff);

        cmd.ExecuteNonQuery();
        if(aff.Value.ToString()!="")
            return (int)aff.Value;
        else
            return 0; 
    }

    //调用存储过程判断学生是否选择了某门课程，函数返回零说明该学生没有选择这门课程，
    //返回值大于零说明该学生选择了这门课
    public int CourseSelected(string stuid, string cursid)
    {
        SqlCommand cmd = new SqlCommand("CourseSelected", stuConn);
        cmd.CommandType = CommandType.StoredProcedure;

        //给存储过程添加参数
        SqlParameter stu = new SqlParameter("@StudentID", SqlDbType.NVarChar, 50);
        stu.Value = stuid;
        cmd.Parameters.Add(stu);

        SqlParameter curs = new SqlParameter("@CourseID", SqlDbType.NVarChar, 50);
        curs.Value = cursid;
        cmd.Parameters.Add(curs);

        SqlParameter aff = new SqlParameter("@rowaffected", SqlDbType.Int, 4);
        aff.Direction = ParameterDirection.Output;
        cmd.Parameters.Add(aff);

        cmd.ExecuteNonQuery();
        if (aff.Value.ToString() != "")
            return (int)aff.Value;
        else
            return 0; 
        
    }

    //调用存储过程判断学生用户输入的学号和选课密码和数据库的是否一样。函数返回零说明输入的学号和选课密码与数据库
    //不一样，返回值大于零说明输入的学号和选课密码合法。
    public int StudentLogin(string stuid, string pwd)
    {
        SqlCommand cmd = new SqlCommand("StudentLogin", stuConn);
        cmd.CommandType = CommandType.StoredProcedure;

        //给存储过程添加参数
        SqlParameter stu = new SqlParameter("@StudentID", SqlDbType.NVarChar, 50);
        stu.Value = stuid;
        cmd.Parameters.Add(stu);

        SqlParameter Pwd = new SqlParameter("@StudentPwd", SqlDbType.NVarChar, 50);
        Pwd.Value = pwd;
        cmd.Parameters.Add(Pwd);

        SqlParameter aff = new SqlParameter("@returnvalue", SqlDbType.Int, 4);
        aff.Direction = ParameterDirection.Output;
        cmd.Parameters.Add(aff);

        cmd.ExecuteNonQuery();
        if (aff.Value.ToString() != "")
            return (int)aff.Value;        
        else
            return 0; 

    }


    //调用存储过程判断学生是否已经登录。
    public int StudentIfLogin(string stuid)
    {
        SqlCommand cmd = new SqlCommand("StudentIfLogin", stuConn);
        cmd.CommandType = CommandType.StoredProcedure;

        //给存储过程添加参数
        SqlParameter stu = new SqlParameter("@StudentID", SqlDbType.NVarChar, 50);
        stu.Value = stuid;
        cmd.Parameters.Add(stu);

        SqlParameter aff = new SqlParameter("@returnvalue", SqlDbType.Int, 4);
        aff.Direction = ParameterDirection.Output;
        cmd.Parameters.Add(aff);

        cmd.ExecuteNonQuery();
        if ((int)aff.Value != 0)
            return (int)aff.Value;
        else
            return 0;
    }


     //调用存储过程判断学生是否在允许的时期内进行选课
    public bool IsValidPeriod()
    {
        SqlCommand cmd = new SqlCommand("IsValidPeriod", stuConn);
        cmd.CommandType = CommandType.StoredProcedure;

        //给存储过程添加参数
        SqlParameter paraPeriodID = new SqlParameter("@PeriodID", SqlDbType.Int,4);
        paraPeriodID.Direction = ParameterDirection.Output;
        cmd.Parameters.Add(paraPeriodID);

        cmd.ExecuteNonQuery();
        if (paraPeriodID.Value.ToString() != "")
        {
            if((int)paraPeriodID.Value>0)
                return true;
            else
                return false;
        }
        else
        {
            return false;
        }
    }

}